<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            /* 给父元素添加flex属性 */
            display: flex;
            width: 800px;
            height: 700px;
            background-color: pink;
            /* 让三个盒子沿着侧轴底侧对齐 */
            /* align-items: flex-end; */
        }

        span {
            width: 150px;
            height: 100px;
            background-color: purple;
            margin: 10px;
        }

        div span:nth-child(2) {
            /* order属性定义项目的排列顺序,默认是0 */
            /* 没有动结构,只是控制css调整排列顺序 */
            order: -1;
        }

        div span:nth-child(3) {
            /* 让第三个盒子下来底侧 */
            align-self: flex-end;
        }
    </style>
</head>

<body>
    <div>
        <span>1</span>
        <span>2</span>
        <span>3</span>
    </div>
</body>

</html>